/* Sudoku - look and feel follows the Delphi / WinForms version: fixed pixel layout, Tahoma 17px. */

:root {
  --face: #f0f0f0;                 /* clBtnFace */
  --selected: #c0dcc0;             /* clMoneyGreen: the highlighted square */
  --font: Tahoma, "Segoe UI", Verdana, Geneva, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
  margin: 0;
  background: #dcdcdc;
  font-family: var(--font);
  overflow: hidden;
}

body.busy, body.busy .form, body.busy .cell, body.busy .btn { cursor: progress; }

#stage {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* The scaler is sized to the scaled puzzle so it centres properly when the window is small. */
.scaler { position: relative; box-shadow: 0 2px 14px rgba(0, 0, 0, .35); }

.form {
  position: absolute;
  left: 0;
  top: 0;
  transform-origin: 0 0;
  background: var(--face);
  user-select: none;
  -webkit-user-select: none;
}

/* The black background the squares sit on (Delphi: Shape1); it shows through as the grid lines. */
.shape { position: absolute; background: #000; }

.cell {
  position: absolute;
  width: 65px;
  height: 65px;
  cursor: default;
}

/* Small helper digits: bold means still possible, italic means ruled out. */
.d {
  position: absolute;
  width: 18px;
  height: 20px;
  font: bold 17px/18px var(--font);
  color: #000;
  cursor: default;
}
.d.imp { font-weight: normal; font-style: italic; }

/* The big result digit: bold if part of the original puzzle, regular if solved. */
.result {
  position: absolute;
  left: 6px;
  top: 2px;
  width: 52px;
  height: 54px;
  font: normal 37px/44px var(--font);
  text-align: center;
  color: #000;
  cursor: default;
}
.result.orig { font-weight: bold; }

/* Buttons, in the style of Windows push buttons */
.btn {
  position: absolute;
  padding: 0;
  font: 16px var(--font);
  color: #000;
  background: #e1e1e1;
  border: 1px solid #adadad;
  border-radius: 0;
  cursor: default;
  white-space: nowrap;
}
.btn:hover { background: #e5f1fb; border-color: #0078d7; }
.btn:active { background: #cce4f7; border-color: #005499; }
.btn:focus-visible { outline: 1px dotted #000; outline-offset: -4px; }
.btn.default { border-color: #0078d7; border-width: 2px; }
u { text-decoration: underline; }

/* ---- Message boxes and the Options dialog ---- */

#overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, .25);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
}
#overlay[hidden] { display: none; }
#overlay, #overlay * { cursor: default; }

.dlg {
  background: var(--face);
  border: 1px solid #5a5a5a;
  box-shadow: 0 6px 24px rgba(0, 0, 0, .5);
  font: 12px "Segoe UI", Tahoma, sans-serif;
  color: #000;
  transform-origin: 0 0;
}
.dlg .title {
  background: #fff;
  padding: 6px 10px;
  font-size: 12px;
  border-bottom: 1px solid #dfdfdf;
}

/* message box */
.msgbox { width: 420px; max-width: 94vw; }
.msgbox .body {
  background: #fff;
  padding: 24px 20px 22px;
  font-size: 15px;
  line-height: 1.35;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  max-height: 70vh;
  overflow: auto;
}
.msgbox .buttons { padding: 12px 14px; display: flex; justify-content: flex-end; gap: 8px; }
.msgbox .buttons .btn { position: static; min-width: 84px; height: 28px; font: 14px "Segoe UI", Tahoma, sans-serif; }

/* options dialog: absolute pixel layout from Options.dfm */
.optform { position: relative; width: 655px; height: 316px; }
.optform .opt { position: absolute; font: 15px var(--font); white-space: nowrap; display: flex; align-items: center; gap: 5px; }
.optform .opt input { margin: 0; width: 15px; height: 15px; }
.optform fieldset {
  position: absolute;
  margin: 0;
  padding: 0;
  border: 1px solid #dcdcdc;
}
.optform legend { font: bold 15px var(--font); padding: 0 3px; margin-left: 6px; }
.optform fieldset .opt { left: 12px; }